Citation and License

Nanoscale Research Letters 2012, 7:328
doi:10.1186/1556-276X-7-328

Published: 21 June 2012

Abstract

Binding features found in biological systems can be implemented into man-made materials
to design nanostructured artificial receptor matrices which are suitable, e.g., for
chemical sensing applications. A range of different non-covalent interactions can
be utilized based on the chemical properties of the respective analyte. One example
is the formation of coordinative bonds between a polymerizable ligand (e.g., N-vinyl-2-pyrrolidone) and a metal ion (e.g., Cu(II)). Optimized molecularly imprinted
sensor layers lead to selectivity factors of at least 2 compared to other bivalent
ions. In the same way, H-bonds can be utilized for such sensing purposes, as shown
in the case of Escherichia coli. The respective molecularly imprinted polymer leads to the selectivity factor of
more than 5 between the W and B strains, respectively. Furthermore, nanoparticles
with optimized Pearson hardness allow for designing sensors to detect organic thiols
in air. The ‘harder’ MoS2 yields only about 40% of the signals towards octane thiol as compared to the ‘softer’
Cu2S. However, both materials strongly prefer molecules with -SH functionality over others,
such as hydrocarbon chains. Finally, selectivity studies with wheat germ agglutinin
(WGA) reveal that artificial receptors yield selectivities between WGA and bovine
serum albumin that are only about a factor of 2 which is smaller than natural ligands.